ELECTRIC PHASE ANGLE OF CELL MEMBRANES
BY KENNETH S. COLE
(From the Department of Physiology, College of Pkysicians and Surgeons, Columbia
Universily, New York)
(Accepted for publication, April 4, 1932)
H6ber (1910, 1912) was able to estimate the electric conductivity
of the interior of red blood corpuscles from measurements made with
high frequency alternating currents. Fricke (1924, 1925, a, b) greatly
extended this work by careful analysis and measurements over a range
of frequencies on the resistance and capacity of suspensions of these
cells. He and McClendon (1926, a, b) both found the cell surface to
behave like a rather good dielectric.
It had an electric capacity that
was practically independent of the frequency and a resistance so high
as to be infinite within the limits of experimental error. But, in view
of the highly specialized functions of these cells, it is not surprising to
find that up to the present they seem to be the only biological systems
showing these characteristics.
Measurements made at different frequencies on the alternating
current impedances of various tissues by Philippson (1921), of muscle
by Sapegno (1930), and of suspension of sea urchin eggs by Cole
(1928, b) have indicated cell surfaces having capacities which vary
with frequency. Measurements on the resistance and capacity of
skin and nerve by Gildemeister and his students (1919-1928), H6zawa
(1925), Lullies (1928, 1930), and Kriiger (1928), on Valonia by Blinks
(1926) and on muscle by Fricke (1931) have further indicated a resist-
ance which also varies with the frequency.
In these latter measure-
ments it has usually been found that the phase angle of this variable
resistance-capacity combination remained more or less constant as
the frequency was varied between wide limits. This resistance-
capacity variation with constancy of phase angle is very similar to the
phenomena of polarization capacity as found at metal-electrolyte
interfaces.
641
The Journal of General Physiology
on December 17